Power transmission mechanism for conversion between linear movement and rotary motion

ABSTRACT

The present invention relates to a spatial cam power transmitting mechanism for the conversion between linear movement and rotary motion. Several transmitting mechanisms for the conversion between reciprocating motion of a roller shaft and rotary motion of an internal groove cam are provided, which do not have a piston and a piston bore. A roller shaft  16  is provided on a upper portion of internal groove cam  6  in a cam casing  15 , and rollers are mounted to the outer end of the roller shaft. The rollers roll in a circumferential direction on the contour line of the groove of the internal groove cam  6.  At the position of fixed rails  4  opposing to the roller shaft  16 , guiding rollers or slide blocks  27  are provided, wherein the fixed rails  4  are provided axially in a lower portion of a cover  1  of the cam casing. The guiding rollers or slide blocks  27  can move up and down respectively in the fixed rails. The power transmitting mechanism is used in an internal combustion engines burning petrol, diesel oil or gas, a stirling engine, a motive engine, such as air or liquid motor, a pump transmitting gas and liquid, a compressor, or other fields which need movement translation.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a transmission mechanism for conversionbetween linear movements and rotary motions, more particularly, to atransmission mechanism for conversion between the reciprocating motionof a roller shaft and the rotary motion of an internal groove cam,furthermore particularly, to a power transmission mechanism forconversion between the reciprocating motion of a piston and a rotarymotion of an internal groove cam.

BACKGROUND OF THE ART

Chinese Patent Application No. 94100421.x, entitled “Internal CombustionEngine having Cam Piston” and published on Dec. 28, 1994, discloses apin shaft (roller shaft) comprising a suspension beam having a free endreceived in an internal groove of a cam, which must be provided with apiston in order to balance the other end of the beam, as shown in FIGS.1, 4 and 5. Therefore, the piston exerts a lateral force to thecylinder, which deteriorates the service life of the piston and thecylinder. Since the projection image of the upper circumferential camcontour completely overlaps with that of the lower circumferential camcontour, the roller generates inverse torque when the pin shaft bearingimpacts from one side to the other side across the groove of thecircumferential cam contour, resulting serious wearing at the crosspoint. In addition, it is extremely inconvenient to replace the rollersand to design a single-cylinder internal combustion engine and amulti-cylinder internal combustion engine by simply combining cylinders.

SUMMARY OF THE INVENTION

The objective of the present invention is to provide several kinds oftransmission mechanisms, in each of which a roller shaft is providedwith rollers near outer ends thereof received in a circumferentialgroove of an internal groove cam, so as to make it possible to form anon-cantilevered structure freely supported at least at two ends inorder to achieve the conversion between parallel reciprocating motion ofthe roller shaft and rotary motions of the internal groove cam whilepistons (vertical motion rods) and cylinders (guiding holes) are notprovided. Accordingly, when cylinders and pitons are provided, there isno lateral force applied to the cylinder walls. It is also convenient toinstall the roller shaft in the mechanism for power transmission, whilerotary direction of the rollers in the cam groove near respective outerends keeps unchanged, which is adapted to be used in the field ofinternal combustion engines, compressors, pumps and pneumatics wheremotion conversion is needed.

Power transmission mechanism for conversion between linear movements androtary motions of the present invention includes a pure rotary motionmember comprising an internal groove cam, reciprocating members includea roller shaft, guiding rollers or sliding blocks 27, primary rollers 9and secondary rollers 37, supports including a cam support (cam box) 15,a cover (cylinder) 1, fixed guiding rails 4. The cam box 15 is providedwith an internal groove cam therein, and a cover 1 fixed at the upperpart of the cam box 15 for closing. The cam box 15 further includes aroller shaft on which a primary roller 9 and a secondary roller 37 aremounted near each end. The rollers roll on the inner circumferential camcontour of the groove so that the roller shaft becomes anon-cantilevered balanced structure freely supported at least at twoends. Guiding rollers or slide blocks 27 are further disposed on theroller shaft at corresponding positions to the fixed guide rails 4connected the lower end of the cover 1 along the axial direction of theinternal groove cam so as to roll or slide up and down along the fixedguide rails 4 as shown in FIG. 1.

The roller shaft may be coupled with a piston rod (vertical motion rod)2 a, or the piston rod (vertical motion rods) 2 a may be connected witha short piston at its upper end which moves up and down through theguiding holes (cylinder opening) 2 in the cover (cylinder) 1. Further, acylinder cover 28 is provided on the cylinder 1 so as to form a chamberwith cylinder opening 2 being sealed, as shown in FIG. 1 a.

One end of the internal groove cam of the present invention is a supportend, and the other end thereof has a cylindrical cavity which has on itsinner circumferential wall a continuous groove having at least two peaksand two valleys with same amplitude. Further, the upper circumferentialcam contour 7 has at least two slots 12 to facilitate installment of theroller shaft with rollers being received into the groove of the internalgroove cam, as shown in FIGS. 2 a, 2 b and 2 c.

The lower end of the internal groove cam of the present invention is anoutput support end which is fixed on a flange connecting with an outputshaft, and the upper end thereof has an end surface having at least twopeaks and two valleys. A continuous groove having the same at least twopeaks and two valleys as those of the upper end is provided along thecircumference of the cavity. Further, the upper circumferential camcontour 7 has at least two slots 12 to facilitate installment of theroller shaft with the rollers being received into the groove of theinternal groove cam, as shown in FIG. 2 c.

The above described internal groove cam may be formed by a combinationof an end surface cam 46 (as the lower circumference cam contour 8),which has a contour with the same at least two peaks and two valleys,and an inner flange cam 3 (as the upper circumference cam contour 7)which corresponds to the end surface cam 46 and has the samecircumferential cam contour, that is, at least two peaks and twovalleys, and at least two slots 12, as shown in FIGS. 2 a and 2 b. Saidinner flange cam 3 may be formed by pressure using a mold.

For replacing rollers without disassembling the whole mechanism, a hole22 communicating with outside is provided inside the groove of theinternal groove cam as shown in FIG. 2 a, or said slots 12 extend fromthe upper circumferential cam contour 7 to the lower circumferential camcontour 8 as shown in FIGS. 1, 2 b and 4. The above described slots 12are both disposed at the lower dead point (the lower stopping position)as shown in FIGS. 4 a, 4 b, or both disposed at the upper dead point(the upper stopping position) as shown in FIG. 4 c, the width of theslots 12 being at least the same as the diameter of the rollers.

The axially downward projection image of the working contour of theupper circumferential cam contour 7 of the internal groove cam accordingto the present invention does not overlap the working contour of thelower circumferential cam contour 8, or does not coincide with the same.Said internal groove cam may have inward-tipping upper circumferentialcam contour 7 and/or lower circumferential cam contour 8 as shown inFIG. 9. The maximum pressure angle of the rising and/or descendingcurve(s) of the circumferential contour of the internal groove camaccording to the present invention ranges from 40 to 80 degree.

The above described piston rods 5 a have a single-leg or multi-legstructure, as shown in FIGS. 6 a to 6 d. The lower end of a bolt 23which contacts the upper end of the piston 2 has a protrusion ring 79,the height of the protrusion portion being less than 1 mm, so as toensure the seal between the bolt 23 and the piston 5 when the piston rod5 a is secured to the piston 5, as shown in FIGS. 6 and 6 e.

Cylinder opening (guiding hole) 2 on the cylinder (cover) 1 according tothe present invention may be designed to correspond to a single cylinderdisposed coaxially with the internal groove cam as shown in FIG. 1, orcylinder openings are disposed at the positions where one circumference50 or two circumferences 50, 51 centered the internal groove cam shaftintersect at least one of a bi-sector to a quinque-sector, as thecylinder openings 2 shown in FIGS. 7 a to 7 f. Since the cylinderopening 2 does not receive any lateral force, it may be formed with aceramic surface.

The roller shaft of the present invention provides a plurality ofsegments which extend from the center to the periphery spaced at a equalangle, as shown as the roller shaft in FIGS. 5 a to 5 d and FIGS. 7 a to7 f, said roller shaft having a through hole 55 at the center. The crosssection of the segments of the above described roller shaft hasrectangular or H shape at positions where the rollers are installed.Said roller shaft may be formed with steel or aluminum-titanium alloyhaving light weight and high strength, or may include carbon fiber andother nonmetallic materials for reducing the reciprocating inertialmass.

The above described roller shaft is articulated with the piston rod, asshown in FIGS. 8, 8 a and 8 b. A side hole 17 is provided at theposition where the piston rod 5 a is installed, and a piston rod 5 a 2 bhaving a “

” shape is mounted on the side hole 17 of the roller shaft by means of apin shaft 54, as shown in FIGS. 6 b 2 and 8. Or, the single-leg pistonrod 5 a having an arcuate lower end engages the roller shaft having anarcuate recess 80 so as to on one hand control the piston rod 5 a toprevent from disengaging from the roller shaft 16 by means of a snapmember and pin shaft 54, and on the other hand make the upper end of thepiston rod swell in the axial plane of the roller shaft by a smallmagnitude. In addition, installing the piston rod in a rigid fixationmanner is involved in the present invention.

In accordance with the present invention, a straight roller shaft 16engages with the internal groove cam 6 or 6 b with a groove having twopeaks and two valleys or four peaks and four valleys. A three-leg rollershaft 16 a engages with the internal groove cam 6 a with a groove havingthree peaks and three valleys. A four-leg roller shaft 16 b engages withthe internal groove cam 6 b having four peaks and four valleys. Afive-leg roller shaft 16 c engages with the internal groove cam havingfive peaks and five valleys.

The outer surface of the primary roller 9 and/or secondary roller 37according to the present invention takes the form of cylinder or taper,which engages with the above described internal groove cam having inwardtipping upper circumferential cam contour 7 and/or lower circumferentialcam contour 8, as shown in FIG. 9, so as to reduce the “Edge Effect”,and to facilitate adjustment of clearance between the primary roller andthe secondary roller in the groove of the internal groove cam. The abovedescribed primary roller 9 always contact the lower circumferential camcontour 8 rather than the upper circumferential cam contour 7, while thesecondary roller 37 always contact the upper circumferential cam contour7 rather than the lower circumferential cam contour 8, so that theprimary roller 9 and the secondary 37 will not invert the torque whenthey reciprocate up and down as the piston rod. The primary roller 9 andthe secondary 37 may not be coaxial with each other, wherein rollingbearings or sliding bearings having rollers closely arranged therein maybe used in order to improve the load capacity.

The above described internal groove cam and rollers are made of steel bycasting or cold working, and the respective rolling surfaces arecarburized or carbonitrided at the carburizing and carbonitridationtemperature so as to make the size of the austenite grain of the surfacegreater than 10, which means the austenite grain is fine enough toprevent from cracking due to skinning initiated internally in order toelongate fatigue life thereof. Then the respective rolling surfaces aresurface hardened at 790-830□ which is lower than the carburizing andcarbonitridation temperature so that the rolling surfaces may have aresidual stress of at least 500 Mpa and a rupture stress of at least2650 Mpa in order to elongate service life thereof.

The guiding roller or sliding block 27 according to the presentinvention has a through hole 55 at the center in which can receive theroller shaft, said hole having a similar outer profile to the crosssection of the roller shaft where the sliding block is installed, asshown in FIGS. 10 a and 10 b. The sliding block 27 is formed with metal(mild steel, mild alloy steel, alloy aluminum etc.,) the sliding surfaceof which is a layer hardened by carburizing or carbonitriding, or aceramic coating layer, or with ceramics so as to improve wearingresistance in order to elongate service life thereof.

Each of the fixed guide rails 4 according to the present invention hastwo opposite sides. Such fixed guide rails 4 disposed at bi-sect toquinque-sect positions on a circumference centered by the axis of theinternal groove cam as shown in FIGS. 7 a to 7 f, the total amount ofwhich may be two to five. A positioning boss 4 c is provided on theouter edge of the fixed guide rail to restrict axial jump of the rollershaft. The surface of the above described fixed guide rail, which isremovable from the guide rail seat 4 d for replacing, may be formed by ametal member, made of such as carbon steel, alloy steel etc, providing asliding surface of the guide rail comprising a layer hardened bycarburizing, carbonitriding, or coating with ceramic, or a nonmetallicmember made of such as ceramics to elongate the service life thereof.

The above described cylinder 1 having a cylinder opening 2 and fixedguide rail 4 d circumferentially disposed at the lower end thereof isintegrally formed, or formed by combining an upper portion 1 a having acylinder opening 2 and a lower portion 1 b having fixed guide rails 4 dcircumferentially disposed at the lower end thereof by means of bolts.

The power transmission mechanism having an internal groove cam 6 aaccording to an embodiment of the present invention utilizes an internalgroove cam with a groove having three peaks and three valleys asmentioned above. The mechanism may have a single cylinder having acylinder opening co-axially disposed with respect to the internal groovecam, or six cylinders having holes 2 a disposed at the six intersectionpositions where two circumferences 50, 51 intersect tri-sectors 25. Thelower ends of six piston rods 5 a fixed to the piston in the singlecylinder or pistons in the six cylinders 2 are equally mounted on thethree segments 16 a 1 of one three-leg roller shaft 16 a, as shown inFIGS. 6 c and 15. Primary rollers 9 and secondary rollers 37 aredisposed on the three segments near the outer ends thereof so as to rollin the groove of the internal groove cam 6 a, in order to form anon-cantilevered structure freely supported at three ends withoutlateral force exerted by the piston to the cylinder walls. Three guidingrollers or sliding blocks 27 are disposed respectively on the threesegments of the roller shaft 16 a at positions corresponding to thethree fixed guide rails 4 axially connected to the lower end of thecylinder at the tri-sect positions on the circumference, so that theycan move along the three fixed guide rails 4 respectively, and thecounteracting force driving the internal groove cam 6 a is applied tothe surfaces of the three fixed guide rails 4 through the three guidingrollers or sliding blocks 27.

If the power transmission mechanism having an internal groove camaccording to another embodiment of the present invention utilizes aninternal groove cam 6 b with a groove having four peaks and fourvalleys, it is also possible to design four cylinder openings 2 that areprovided at the four intersection positions where one circumference 50centered by the axis of the internal groove cam intersect thequarter-sectors 34, as shown in FIG. 7 b, or to design eight cylinderopenings 2 that are provided at the eight intersection positions wheretwo circumference 50, 51 intersect the quarter-sectors 34 as shown inFIG. 7 e. The lower parts of the four or eight piston rods 5 being fixedto the pistons 5 through the cylinder openings 2 of the four cylindersor eight cylinders are mounted on the four segments of a four-leg rollershaft. Four secondary rollers 37 and four primary rollers 9 are mountedon the four segments near the four outer ends of the roller shaft 16 brespectively so as to roll in the groove of the internal groove cam 6 bin order to form a non-cantilevered structure freely supported at fourends without lateral force by the piston exerted to the cylinder. Fourguiding rollers or sliding blocks 27 are disposed at the positions wherethe four segments of the roller shaft 16 b at positions corresponding tothe four fixed guide rails 4 axially connected to the lower end of thecylinder at the quarter-sect positions on a circumference, so that theycan move along the four fixed guide rails 4, and the counteracting forcedriving the internal groove cam 6 b is applied to the surface of thefour fixed guide rails 4 through the four guiding rollers or slidingblocks 27, as shown in FIGS. 14 and 16.

The power transmission mechanism having an internal groove cam accordingto further another embodiment of the present invention utilizes aninternal groove cam with having five peaks and five valleys, which fitten cylinder openings 2 that are provided at the ten intersectionpositions where two circumferences 50, 51 intersect quinque-sectors 68,as shown in FIG. 7 f. Such internal groove cam fits a five-leg rollershaft 16 c. The lower part of the ten piston rods 5 a fixed to the tenpistons 5 through the ten cylinder openings 2 are equally mounted on thefive segments of the five-leg roller shaft respectively. Primary rollers9 and secondary rollers 37 are provided on the four segments near theouter ends thereof so as to roll in the groove of the internal groovecam 6 a, in order to form a non-cantilevered structure freely supportedat four ends without lateral force exerted by the piston to the cylinderwalls. Four guiding rollers or sliding blocks 27 are disposedrespectively on the four segments of the roller shaft 16 a at positionscorresponding to the four fixed guide rails 4 axially connected to thelower end of the cylinder at the tri-sect positions on thecircumference, so that they can move along the four fixed guide rails 4respectively, and the counteracting force driving the internal groovecam 6 a is applied to the surfaces of the four fixed guide rails 4through the four guiding rollers or sliding blocks 27.

If an internal groove cam having two peaks and two valleys is utilizedin the power transmission mechanism having an internal groove camaccording to the present invention rotates for one round, thereciprocating assembly (the piston rod 5, the primary rollers 9, thesecondary rollers 37, the roller shaft 16, the guiding rollers orsliding blocks 27) reciprocates up and down for four times. If aninternal groove cam having three peaks and three valleys rotates for oneround, the reciprocating assembly reciprocates up and down for sixtimes. If an internal groove cam having four peaks and four valleysrotate for one round, the reciprocating assembly reciprocates up anddown for eight times.

It is obvious that the advantages include: 1) The present invention hasa simple structure to achieve the conversion between reciprocatingmotions of a roller shaft and the rotary motion of a internal groove camwithout provision of a cylinder and a piston. 2) Even a piston isprovided, there is no lateral force exerted to the cylinder wall so thatthe service life of the piston and the cylinder can be improved. 3) Ashort piston can be designed without limitation of the shape of thepiston to an ellipse and manufactured easily. 4) There is no inverse thetorque produced by the roller so that the service life thereof can beimproved. 5) The primary and secondary rollers may be replaced withoutthe need of disassembling so that it is efficient for maintenance andservice. 6) The power transmission mechanism for motion conversion ofpresent invention may be applied to the field of internal and externalcombustion engine, pneumatic or hydraulic motor or pump.

DESCRIPTION OF THE DRAWINGS

The structure of the embodiments of the present invention is illustratedin the following drawings, in which:

FIG. 1 is a front cross section view illustrating the motion conversionmechanism between a roller shaft in parallel reciprocation movement andan internal groove cam in rotary motion.

FIG. 1 a is a front cross section view illustrating the powertransmission mechanism of an internal groove cam having single cylinder.

FIG. 2 a is a cross section view of an internal groove cam 6 b havingfour peaks, four valleys and four slots 12 which is formed by combiningan end surface cam 46 and an inner flange cam 3.

FIG. 2 b is a cross section view of an internal groove cam 6 b havingthree peaks, three valleys and three slots 12 which is formed bycombining an end surface cam 46 and an inner flange cam 3.

FIG. 2 c illustrates an internal groove cam 6 having two peaks and twovalleys and two slots 12.

FIG. 3 is a partially cross section view of the pressurized lubricantoil path.

FIG. 4 a is a schematically view illustrating the positions of theprimary rollers near the both ends of the roller shaft 16 in the grooveof the internal groove cam 6 having two peaks and two valleys, in whichthe circumferential wall is shown in a stretched state and an enclosingblock 13 is not installed.

FIG. 4 b is a schematically view illustrating the positions of the threeprimary rollers 9 on the three segments of the three-leg roller shaft 16a in the groove of the internal groove cam 6 b having three peaks andthree valleys, in which the circumferential wall is shown in a stretchedstate and an enclosing block 13 is not installed.

FIG. 4 c is a schematically view illustrating the positions of the fourprimary rollers 9 on the four segments of the four-leg roller shaft 16 ain the groove of the internal groove cam 6 b having four peaks and fourvalleys, in which the circumferential wall is shown in a stretched stateand an enclosing block 13 is not installed.

FIG. 5 a illustrates a straight roller shaft 16 on which a piston rod 5a 2 b having a “

” shape at its lower part is mounted through a central hole 55 in centerand two side holes 17 in two of the segments of the roller shaftrespectively.

FIG. 5 b 1 and 5 b 2 are front and plan view of a three-leg roller shaft16 a which has a central hole 55 and three equally spaced segments onwhich six side holes 17 for receiving the “

” shaped lower parts of six piston rods 5 a 2 b are providedrespectively.

FIG. 5 c 1 and 5 c 2 are front and plan view of a four-leg roller shaft16 b which has a central hole 55 and four equally spaced segments onwhich eight side holes 17 for receiving the “

” shaped lower parts of six piston rods 5 a 2 b are providedrespectively.

FIG. 5 d is a plan view of a five-leg roller shaft 16 d which has acentral hole 55 and five equally spaced segments.

FIG. 6 is a partially cross section view illustrating how the piston 5is fixed to the piston rod 5 a by means of a bolt 23 having a ring 79.

FIG. 6 a is a schematic view illustrating the installment state of thelower part of the single-leg piston rod 5 a 1 and the roller shaft.

FIG. 6 b 1 is a schematic view illustrating the installment state of thelower part of the two-leg piston rod 5 a 2 a and the roller shaft.

FIG. 6 b 2 is a schematic view illustrating the installment state of thegate-shaped lower parts of the two-leg piston rod 5 a 2 b and the rollershaft.

FIG. 6 c is a schematic view illustrating the installment state of thelower parts of the three-leg piston rod 5 a 3 and the correspondingroller shaft 16 a.

FIG. 6 d is a schematic view illustrating the installment state of thelower parts of the four-leg piston rod 5 a 4 and the correspondingroller shaft 16 b.

FIG. 6 e is a front plan view of a bolt 23.

FIG. 7 a is a schematically plan view illustrating two cylinder openings2 that are provided at the two positions where a circumference 50intersects the bi-sectors 67, the straight roller shaft 16 having twoequally spaced segments and two fixed guide rails 4 located at positionswhich divides the circumference into two equal parts.

FIG. 7 b is a schematically plan view illustrating four cylinderopenings 2 that are provided at the four positions where a circumference50 intersects the quarter-sectors 34, the straight roller shaft 16having four equally spaced segments and four fixed guide rails 4 locatedat positions which divides the circumference into four equal parts.

FIG. 7 c is a schematically plan view illustrating four cylinderopenings 2 that are provided at the four positions where twocircumferences 50, 51 intersect the bi-sectors 67, the straight rollershaft 16 having two equally spaced segments and two fixed guide rails 4located at positions which divides the circumference into two equalparts.

FIG. 7 d is a schematically plan view illustrating six cylinder openings2 that are provided at the six positions where two circumferences 50, 51intersect the tri-sectors 25, the straight roller shaft 16 having threeequally spaced segments and three fixed guide rails 4 located atpositions which divides the circumference into three equal parts.

FIG. 7 e is a schematically plan view illustrating eight cylinderopenings 2 that are provided at the eight positions where twocircumferences 50,51 intersect the quarter-sectors 34, the straightroller shaft 16 having four equally spaced segments and four fixed guiderails 4 located at positions which divides the circumference into fourequal parts.

FIG. 7 f is a schematically plan view illustrating ten cylinder openings2 that are provided at the ten positions where two circumference 50, 51intersect the quinque-sectors 68, the straight roller shaft 16 havingfive equally spaced segments and five fixed guide rails 4 located atpositions which divides the circumference into five equal parts.

FIG. 8 is a view showing the assembly of the piston rod 5 a 2 b having a“

”-shaped lower part and a roller shaft having side holes 17.

FIG. 8 a 1 is a front view illustrating the roller shaft 16 having anarcuate recess 80, on which a single leg piston rod 5 a 1 with anarcuate lower end and a sliding block 27(or snap member 81) are mounted.

FIG. 8 a 2 is a left side section view of FIG. 8 a 1.

FIG. 8 b 1 is a front view illustrating the connection of the single legpiston rod 5 a 1 having an arcuate lower end is articulated with theroller shaft 16 having an arcuate recess 80.

FIG. 8 b 2 is a plan view of FIG. 8 b 1.

FIG. 9 is a partially cross section view illustrating that status whenthe primary and secondary rollers 9 a and 37 having a taper shape arelocated in the inner circumferential groove formed by the inward-tippingupper circumferential cam contour 7 and lower circumferential camcontour 8 of the internal groove cam.

FIG. 10 a is a partially cross section view illustrating the fixed guiderail seats 4 d having a small nozzle hole 78 which aligns with therolling bearing for the primary roller 9.

FIG. 10 b is a partially cross section view illustrating the oil pathwhich directs from the hole 66 on the guide rail surface 4 a, 4 b of thefixed guide rail 4 and the sliding block 27 to the primary roller 9 viaa central hole in the roller shaft when the primary roller 9 is mountedwith a plain bearing.

FIG. 11 is a front cross section view illustrating a single-cylinder andfour-stroke internal combustion engine having the internal groove cam 6.

FIG. 12 a is a section view illustrating a double-cylinder andfour-stroke internal combustion engine, and having the internal groovecam 6 having timing belt provided outside.

FIG. 12 b 1 is a section view illustrating a double-cylinder andfour-stroke internal combustion engine having the internal groove cam 6.

FIG. 12 b 2 is a view illustrating a double-cylinder and four-strokeinternal combustion engine having the internal groove cam 6.

FIG. 13 a is a section view illustrating a four-cylinder and four-strokeinline internal combustion engine having the internal groove cam 6 witha cam groove having two peaks and two valleys.

FIG. 13 b is a schematically view illustrating a four-cylinder andfour-stroke inline internal combustion engine having the internal groovecam 6 with a cam groove having two peaks and two valleys.

FIG. 14 a is a section view illustrating a four-cylinder and four-strokeinternal combustion engine with cylinders being arrangedcircumferentially having the internal groove cam 6 with a cam groovehaving two peaks and two valleys.

FIG. 14 b a schematically view illustrating a four-cylinder andfour-stroke internal combustion engine with cylinders being arrangedcircumferentially having the internal groove cam 6 with a cam groovehaving two peaks and two valleys.

FIG. 15 a is a section view illustrating a six-cylinder and four-strokeinternal combustion engine with cylinders being arranged along twocircumferences having the internal groove cam 6 with a cam groove havingthree peaks and three valleys.

FIG. 15 b a schematically view illustrating a six-cylinder andfour-stroke internal combustion engine with cylinders being arrangedalong two circumferences having the internal groove cam 6 with a camgroove having three peaks and three valleys.

FIG. 16 a is a section view illustrating an eight-cylinder andfour-stroke internal combustion engine with cylinders being arrangedalong two circumferences having the internal groove cam 6 with a camgroove having four peaks and four valleys.

FIG. 16 b a schematically view illustrating a eight-cylinder andfour-stroke internal combustion engine with cylinders being arrangedalong two circumferences having the internal groove cam 6 with a camgroove having four peaks and four valleys.

FIG. 17 is a partially section view illustrating a one-way valve seat 77on the cylinder 1.

FIG. 17 a is a partially section view illustrating a reciprocatingbooster pump mounted on the cylinder 1 which communicates with the cambox.

FIG. 17 b is a section view illustrating a reciprocating booster pumpmounted on the cylinder 1 which dose not communicate with the cam box.

FIG. 18 a is a front cross section view illustrating a sterling enginehaving two sets of power transmission mechanism having the internalgroove cam in single cylinder.

FIG. 18 b is a graph illustrating the phase of the primary rollers 9 onthe stretched lower circumferential cam contour 8, which are provided inthe power transmission mechanism having the internal groove cam in thepower cylinder of air distributions cylinder respectively of thesterling engine.

FIG. 19 a is a section view illustrating a pneumatic or hydraulic motorhaving two sets of power transmission mechanism having the internalgroove cam in single cylinder.

FIG. 19 b is a graph illustrating the phase of the primary rollers 9 onthe stretched lower circumferential cam contour 8, which are providednear each end of the roller shaft respectively in the power transmissionmechanism having two sets of internal groove cam in single cylinder inthe pneumatic or hydraulic motor.

FIG. 20 is a section view illustrating a pump having the powertransmission mechanism having the internal groove cam in singlecylinder.

FIG. 21 is a section view illustrating a single-cylinder anddouble-stroke internal combustion engine and having the internal groovecam 6.

REFERENCE NUMERALS LIST

1 cylinder (cover), 2 cylinder opening (guiding hole), 3 inner flangecam, 4 fixed guide rail, 4 a, 4 b guide rail surfaces mounted on thefixed guide rail seat, 4 c positioning boss of the fixed guide railseat, 4 d fixed guide rail seat, 5 piston, 5 a piston rod, 5 a 1single-leg piston rod, 5 a 2 a two-leg piston rod, 5 a 2 b “

”-shaped two-leg piston rod, 5 a 3 three-leg piston rod, 5 a 4 four-legpiston rod, 6 internal groove cam with a cam groove having two peaks andtwo valleys, 6 a internal groove cam with a cam groove having threepeaks and three valleys, 6 b internal groove cam with a cam groove havefour peaks and four valleys, 6 i through hole in the upper and lower endsurface of the internal groove cam, 7 upper circumferential cam contourof the internal groove cam, 8 lower circumferential cam contour of theinternal groove cam, 9 roller, 9 a primary roller having a taper shape,10 output shaft, 11 valve, 12 slot, 13 slot enclosing block, 14 centralhole at the upper end of the internal groove cam, 15 cam support (cambox), 16 straight roller shaft, 16 a three-leg roller shaft, 16 a 1three segments of the three-leg roller shaft, 16 b four-leg rollershaft, 16 b 1 four segments of the four-leg roller shaft, 16 c five-legroller shaft, 17 side hole of the roller shaft, 18 garter spring, 19 airport, 20 partially cut line, 21 bearing, 22 through hole in the grooveof the internal groove cam, 23 fixing bolt, 24 oil ring, 25 tri-sector,26 scavenging port, 27 guiding roller or sliding block, 28 cylindercover, 29 peak of the circumferential cam contour, 30 valley of thecircumferential cam contour, 31 power (intake) curve contour, 32 exhaust(compress) curve contour, 33 a upper end surface bearing, 33 a 1circular oil channel of the upper end surface bearing, 33 b lower endsurface bearing, 34 quarter-sector, 35 camshaft for valve system, 36timing gear, 37 secondary roller, 37 a secondary roller having a tapershape, 38 transmission gear, 39 fixing key, 40 bevel gear, 41 timingchain or timing belt, 42 oil pump, 43 timing gear, 44 leaf valve, 45side hole of the cam box, 46 end surface cam, 47 bevel gear on the airdistribution transmission shaft, 48 air distribution transmission shaft,49 timing gear for the air distribution transmission shaft, 50 outercircumference, 51 inner circumference, 52 broken line forsynchronization, 53 thread hole for engaging the enclosing block 13, 54pin shaft, 55 through hole, 56 heater, 57 recuperator, 58 cooler, 59transmission shaft, 60 reversing valve, 60 a reversing valve seat, 60 breversing valve core, 61 reversing gear, 62 intake port, 63 exhaustport, 64 air channel, 65 oil channel, 66 oil hole, 67 bi-sector, 68quinque-sector, 69 one-way intake valve, 70 one-way exhaust valve, 71free piston, 73 pneumatic reciprocating pump, 74 guiding rod, 75 inletof the intake pipe, 76 outlet of the exhaust pipe, 77 one-way valveseat, 78 small nozzle hole, 79 ring, 80 arcuate recess, 81 snap member.

MODE OF CARRYING OUT THE INVENTION Embodiment 1

A single-cylinder and two-stroke internal combustion engine comprising apower transmission mechanism having an internal groove cam is shown inFIG. 21. The engine comprises an internal groove cam 6, a cylinder cover28, a cylinder having a cylinder opening 2, an exhaust port 63 and ascavenging port 26, a piston 5 and a piston rod 5 a 2 a, two primaryrollers 9, two secondary rollers 37, two guiding rollers or slidingblocks 27, a roller shaft 16, two fixed guide rails 4, an intake port62, and a cam box 15. The internal groove cam is provided in the cam box15. The cylinder 1 having the cylinder cover 28 at the upper partthereof and the cylinder opening 2 axially disposed therewith is fixedto the cam box 15. A roller shaft 16 is disposed at the lower part ofthe piston rod 5 a 2 a fixed to the piston 5 in the cylinder opening 2,and perpendicular to the cylinder opening 2. Two primary rollers 9 andtwo secondary rollers 37 are disposed near the two ends of the rollershaft at the positions corresponding to the circumferential cam contourso that they are received in the groove of the internal groove camthrough two slots 12 in the upper circumferential cam contour of theinternal groove cam 6 to roll following the circumferential contour,which forms a non-cantilevered structure freely supported at two ends.Two guiding rollers or slide blocks 27 are further disposed on theroller shaft at corresponding positions to the fixed guide rails 4connected with the lower end of the cover 1 in the axial direction ofthe internal groove cam so as to roll or slide up and down along thefixed guide rails 4. An intake port 50 with a leaf valve 44 are providein the side of the cam box 15, and meanwhile, an exhaust port 19 and ascavenging port 26 communicating with the cam box are provided in thewall of the cylinder.

Embodiment 2

A single-cylinder and four-stroke internal combustion engine comprisinga power transmission mechanism having an internal groove cam is shown inFIG. 11. The engine comprises an internal groove cam 6, a cylinder cover28 on which a part of members forming the valve system, such as a valveand a camshaft and etc., are mounted, a cylinder 1 having a cylinderopening 2, a piston 5 and a piston rod 5 a 2 a, two primary rollers 9,two secondary rollers 37, two guiding rollers or sliding blocks 27, aroller shaft 16, two fixed guide rails 4, a cam box 15. The internalgroove cam 6 is provided in the cam box 15. The cylinder 1 having thecylinder cover 28 is fixed to the cam box 15. Two primary rollers 9 andtwo secondary rollers 37 are disposed near the two ends of the rollershaft at the positions corresponding to the circumferential cam contourso that they are received in the groove of the internal groove camthrough two slots 12 in the upper circumferential cam contour of theinternal groove cam 6 to roll following the circumferential contour,which forms a non-cantilevered structure freely supported at two ends.Two guiding rollers or slide blocks 27 are further disposed on theroller shaft at corresponding positions to the fixed guide rails 4connected with the lower end of the cover 1 in the axial direction ofthe internal groove cam so as to roll or slide up and down along thefixed guide rails 4.

If the internal groove cams 6 utilized in both Embodiment 1 andEmbodiment 2 has a cam groove with two peaks and two valleys, the camshaft 35 of an four-stroke internal combustion engine rotates for oneround as the cam rotate for one round, at the same time, the pistonworks once. The piston will work twice if said internal combustionengine is replaced by a double-stroke internal combustion engine. If theinternal groove cams 6 has a cam groove with three peaks and threevalleys, the camshaft 35 of a four-stroke internal combustion enginerotates for three rounds as the cam rotates for two rounds, at the sametime, the piston works three times. The piston will work six times ifsaid internal combustion engine is replaced by a two-stroke internalcombustion engine. If the internal groove cams 6 b has a cam groove withfour peaks and four valleys, the camshaft 35 for valve system of afour-stroke internal combustion engine rotates for two rounds as the camrotates for one round, and the piston work twice. The piston will workfour times if said internal combustion engine is replaced by atwo-stroke internal combustion engine.

Embodiment 3

A double-cylinder and four stroke inline internal combustion enginecomprises a power transmission mechanism having an internal groove cam.The engine comprises an internal groove cam 6 or 6 b, a cylinder cover28 on which a part of members forming the valve system, such as a valveand a camshaft and etc., are mounted, a cylinder 1 having two cylinderopenings 2 disposed at the positions where one circumference 50intersects the bi-sectors 67, two pistons 5, two piston rods 5 a, twoprimary rollers 9, two secondary rollers 37, two guiding rollers orsliding blocks 27, a roller shaft 16, two fixed guide rails 4, a cam box15. The internal groove cam 6 is provided in the cam box 15. Thecylinder 1 having the cylinder cover 28 at the upper part thereof isfixed to the cam box 15. The lower parts of the two piston rods 5 afixed to two pistons 5 in the two cylinder openings 2 of the cylinder 1are mounted on the roller shaft 16 so that the two pistons 5 and theroller shaft 16 form a structure reciprocating up and down together as aunit. Two primary rollers 9 and two secondary rollers 37 are disposednear the two ends of the roller shaft at the positions corresponding tothe circumferential cam contour so that they are received in the grooveof the internal groove cam through two slots 12 in the uppercircumferential cam contour of the internal groove cam 6 to rollfollowing the circumferential contour, which forms a non-cantileveredstructure freely supported at two ends. Two guiding rollers or slideblocks 27 are further disposed on the roller shaft at correspondingpositions to the two inline fixed guide rails 4 connected with the lowerend of the cover 1 in the axial direction of the internal groove cam atpositions where the roller shaft is divided equally, to roll or slide upand down along the fixed guide rails 4. As shown in FIGS. 7 a, 12 a and12 b, the cams for charging air and exhausting air in the abovementioned two cylinders are designed to be in opposite directions, thatis, their phase difference is 180 degree, so that one piston is incompression stroke while the other is in intake stroke when the twopistons are moving upward, and one piston is in power stroke while theother is in exhaust stroke when the two pistons 5 are moving downward.The rotation for one round of the internal groove cam 6 will bring thecamshaft 35 for valve system to rotate for one round, so as to make eachpiston works once. If the internal groove cam 6 b rotates for one round,the camshaft 35 for valve system rotates for two rounds, then each ofthe two pistons 5 works twice. It is apparent that efficiency of thecylinder and power per liter are improved in the internal combustionengine using the present invention.

Embodiment 4

A four-cylinder and four-stroke inline internal combustion enginecomprises a power transmission mechanism having an internal groove camas shown in FIG. 13. The engine comprises an internal groove cam 6 or 6b, a cylinder cover 28 on which a part of members forming the valvesystem, such as a valve and a camshaft and etc., are mounted and havingfour combustion chambers, a cylinder 1 having four cylinder openings 2linearly arranged at the four positions where two circumference 50, 51intersects the bi-sectors 67, four pistons 5, four piston rods 5 a, twoprimary rollers 9, two secondary rollers 37, two guiding rollers orsliding blocks 27, a roller shaft 16, two fixed guide rails 4, a cam box15. The internal groove cam 6 is provided in the cam box 15. Thecylinder 1 having the cylinder cover 28 at the upper part thereof andlinearly arranged with four cylinder openings 2 is fixed to the cam box15. The lower parts of the four piston rods 5 a fixed to the fourpistons 5 in the four cylinders holes 2 are all mounted on the rollershaft 16 which is perpendicular to the piston rods, so that the fourpiston rods S and the roller shaft 16 reciprocates up and down insynchronism as a unit. Two primary rollers 9 and two secondary rollers37 are disposed near the two ends of the roller shaft at the positionscorresponding to the circumferential cam contour so that they arereceived in the groove of the internal groove cam through two slots 12in the upper circumferential cam contour of the internal groove cam 6 toroll following the circumferential contour, which forms anon-cantilevered structure freely supported at two ends. Two guidingrollers or slide blocks 27 are further disposed on the roller shaft atcorresponding positions to the fixed guide rails 4 connected with thelower end of the cover 1 in the axial direction of the internal groovecam so as to roll or slide up and down along the fixed guide rails 4.

The cams for charging and exhausting air respectively corresponding totwo cylinders may be designed to have the same opening or closing anglesso that the two cylinders intake, compress, work and exhaust insynchronism, while the cams for charging and exhausting air respectivelycorresponding to the other two cylinders may be designed to have thesame opening or closing angles so that the other two cylinders intake,compress, work and exhaust in synchronism too. It is designed that phasedifference between the former two cylinders and the latter two cylindersis 180 degree so that the two cylinders are in power stroke while theother two cylinders are in exhaust stroke when the four pistons are allmoving upward. If the internal groove cam 6 rotates for one round, eachof the four cylinders work once, that is, four times in total. If theinternal groove cam 6 b rotates for one round, each of the fourcylinders works twice, that is, eight times in total. It is apparentthat efficiency of the cylinder and power per liter are improved in theinternal combustion engine using the present invention.

In the above Embodiments 2, 3 and 4, the camshaft 35 for valve systemmounted on the cylinder cover 28 transmits motion between a timing gear49 disposed at the outer end of the transmission shaft 48 for valvesystem and a timing gear 36 disposed at one end of the camshaft 35 forvalve system through the engagement of a bevel gear 40 that is disposedat the lower end of the internal groove cam 6 with a bevel gear 47 thatis disposed at one end of the transmission shaft 48 for valve systemhorizontally disposed at the lower part of the cam box 15 by means of atiming belt or chain 41, as shown in the transmission part for valvesystem shown in FIGS. 11 and 12 a.

Embodiment 5

A four-cylinder and four-stroke internal combustion engine with fourcylinders disposed circumferentially and spaced by 90 degrees comprisesan internal groove cam 6 b. The engine comprises an internal groove cam6 b, a cylinder 1 having four cylinder openings 2 disposed at the fourpositions where one circumference 50 intersects quarter-sectors 34, fourcylinder covers 28 on each of which a part of members forming the valvesystem, such as a valve and a camshaft and etc., are mounted, fourpistons 5, four piston rods 5 a, four primary rollers 9, four secondaryrollers 37, four guiding rollers or sliding blocks 27, a four-leg rollershaft 16 b, four fixed guide rails 4 extending axially and equallydisposed on a circumference, a cam box 15. The internal groove cam 6 bis provided in the cam box 15. The cylinder 1 having the above-mentionedfour cylinder openings 2 and four cylinder covers 28 at the upper partthereof is fixed to the cam box 15. The lower parts of the four pistonrods 5 a fixed to the four pistons 5 in the four cylinders 2 are mountedrespectively on the four segments of the four-leg roller shaft 16 bwhich is perpendicular to the piston rods, so that the four pistons 5and the four-leg roller shaft 16 b reciprocates up and down insynchronism as a unit. Four primary rollers 9 and four secondary rollers37 are disposed near the outer ends of the segments of the four-legroller shaft 16 b respectively at the positions corresponding to thecircumferential cam contour so that they are received in the groove ofthe internal groove cam through four slots 12 in the uppercircumferential cam contour of the internal groove cam 6 to rollfollowing the circumferential contour, which forms a non-cantileveredstructure freely supported at four ends. Four guiding rollers or slideblocks 27 are further disposed on the four-leg roller shaft atcorresponding positions to the fixed guide rails 4 connected with thelower end of the cylinder 1 and extending in the axial direction of theinternal groove cam so as to roll or slide up and down along the fixedguide rails 4.

The cams for charging and exhausting air of two camshafts 35 on twocorresponding cylinder covers 28 disposed diagonally may be designed tohave the same opening or closing angles so that the two cylindersintake, compress, work and exhaust in synchronism, while the cams forcharging and exhausting air of two camshafts 35 on the other twocorresponding cylinder covers 28 disposed diagonally may be designed tohave the same opening or closing angles so that the other two cylindersintake, compress, work and exhaust in synchronism too. It is designedthat phase difference between the former two cylinders and the lattertwo cylinders is 180 degree so that the two cylinders are in compressionstroke while the other two cylinders are in exhaust stroke when the fourpistons are all moving upward; the two cylinders are in power strokewhile the other two cylinders are in intake stroke when the four pistonsare all moving downward.

The pistons reciprocate eight times when the above internal groove cam 6b with a groove having four peaks and four valleys rotates for oneround, that is, each of the four cylinders works twice, that is, eighttimes in total. It is apparent that the efficiency of the cylinder andpower per liter are improved four times.

Embodiment 6

A six-cylinder and four-stroke internal combustion engine comprises apower transmission mechanism having an internal groove cam. The enginecomprises an internal groove cam 6 a, three cylinder covers 28 each ofwhich has two combustion chambers, and on each of which a part ofmembers forming the valve system, such as a valve and a camshaft andetc., are mounted, a cylinder 1 in which six cylinder openings 2 aredisposed at the positions where two circumference 50, 51 intersecttri-sector 25, wherein 2 a, 2 b, 2 c are located at the tri-sectpositions on the same outer circumference and 2 d, 2 e, 2 f are locatedat the tri-sect positions on another same inner circumference as shownin FIG. 7 d, six pistons 5, six piston rods 5 a, three primary rollers9, three secondary rollers 38, three guiding rollers or sliding blocks27, a three-leg roller shaft 16 a, three fixed guide rails 4 extendingaxially and disposed at the tri-sect positions on the circumference, acam box 15. The internal groove cam 6 a is provided in the cam box 15.The cylinder 1 having six cylinder openings 2 and the three cylindercovers 28 at the upper part thereof is fixed to the cam box 15. Thelower parts of the six piston rods 5 a fixed to the six pistons 5 in thesix cylinder openings 2 are equally mounted on three segments of thethree-leg roller shaft 16 a which is perpendicular to the piston rods,so that the six pistons 5 and the three-leg roller shaft 16 areciprocates in synchronism up and down as a unit. Three primary rollers9 and three secondary rollers 37 are disposed near the outer ends of thethree segments of the three-leg roller shaft 16 b respectively at thepositions corresponding to the circumferential cam contour so that theyare received in the groove of the internal groove cam through threeslots 12 in the upper circumferential cam contour of the internal groovecam 6 to roll following the circumferential contour, which forms anon-cantilevered structure freely supported at three ends. Three guidingrollers or slide blocks 27 are further disposed on the three-leg rollershaft at corresponding positions to the fixed guide rails 4 connectedwith the lower end of the cylinder 1 and extending in the axialdirection of the internal groove cam so as to roll or slide up and downalong the fixed guide rails 4.

The bevels gears 40 that are disposed respectively at one end of each ofthe three camshaft for valve systems 35 on the above three cylindercovers 28 all engage with the bevel gear 47 that is disposed at theupper end of the transmission shaft 48 for valve system, which extendsupwardly from the central hole 14 on the upper end of the internalgroove cam via the through hole 55 at center of the roller shaft, inorder to make each of the three camshaft for valve systems 35 to rotatefor three rounds when the internal groove cam 6 a rotates for tworounds.

The cams for charging and exhausting air of the camshafts 35 for valvesystems corresponding to the above three cylinders 2 a, 2 b, 2 c on theouter circumference are designed to have the same magnitude anddirection for the opening or closing angle, so that the three cylindersintake, compress, work and exhaust in synchronism, while cams forcharging and exhausting air of the camshafts 35 for valve systemscorresponding to the above three cylinders 2 d, 2 e, 2 f on the innercircumference are designed to have the same magnitude and direction forthe opening or closing angle, so that the other three cylinders intake,compress, work and exhaust in synchronism. It is designed to have adifference of 180 degrees between the phase of cams for charging andexhausting air of the camshafts 35 for valve systems for the above threecylinders 2 a, 2 b, 2 c and the phase of cams for charging andexhausting air of the camshafts 35 for valve systems for the other threecylinders so that three cylinders on the same circumference are incompression stroke while the other three cylinders are in exhaust strokewhen the six cylinders are all moving upward, and three cylinders on thesame circumference are in power stroke while the other three cylindersare in intake stroke when the six cylinders are all moving downward.Therefore, all the six cylinders work three times when the aboveinternal groove cam 6 a rotates for two rounds, that is, eighteen timesin total. It is apparent that efficiency of the cylinder and work perliter in the internal combustion engine are improved three times.

Embodiment 7

An eight-cylinder and four-stroke internal combustion engine comprises apower transmission mechanism having an internal groove cam 6 b. Theengine comprises an internal groove cam 6 b with a cam groove havingfour peaks and four valleys, four cylinder covers 28 on each of which apart of members forming the valve system, such as a valve and a camshaftand etc., are mounted, a cylinder 1 having eight cylinder openings 2disposed at the positions where two circumferences 50, 51 intersect thequarter-sector 34 as shown in FIG. 7 b, eight pistons 5, eight pistonrods 5 a, four primary rollers 9, four secondary rollers 37, fourguiding rollers or sliding blocks 27, a four-leg roller shaft 16 b, fourfixed guide rails 4 axially disposed at the quarter-sect positions onthe circumference, a cam box 15. The internal groove cam 6 b is providedin the cam box 15. The cylinder 1 having eight cylinder openings 2 andfour cylinder covers 28 at the upper part thereof is fixed to the cambox 15. The lower parts of the eight piston rods 5 a fixed to the eightpistons 5 in the eight cylinders 2 are equally mounted on four segments16 b 1 of the four-leg roller shaft 16 b which is perpendicular to thepiston rods, so that the eight pistons 5 and the four-leg roller shaft16 b reciprocates up and down in synchronism as a unit. Four primaryrollers 9 and four secondary rollers 37 are disposed near the outer endsof the four segments of the four-leg roller shaft 16 b respectively atthe positions corresponding to the circumferential cam contour so thatthey are received in the groove of the internal groove cam through fourslots 12 in the upper circumferential cam contour of the internal groovecam 6 to roll following the circumferential contour, which forms anon-cantilevered structure freely supported at four ends. Four guidingrollers or slide blocks 27 are further disposed on the four-leg rollershaft at corresponding positions to the fixed guide rails 4 connectedwith the lower end of the cylinder 1 and extending in the axialdirection of the internal groove cam so as to roll or slide up and downalong the fixed guide rails 4.

The cams for charging and exhausting air of the camshafts 35 for valvesystems corresponding to the above four cylinders 2 a, 2 b, 2 c and 2 don the outer circumference may be designed to have the same magnitudeand direction for the opening or closing angle, so that the fourcylinders intake, compress, work and exhaust in synchronism, while camsfor charging and exhausting air of the camshafts 35 for valve systemscorresponding to the above four cylinders 2 e, 2 f, 2 g, 2 h on theinner circumference may be designed to have the same magnitude anddirection for the opening or closing angle, so that the other fourcylinders intake, compress, work and exhaust in synchronism. It isdesigned to have a difference of 180 degrees between the phase of camsfor charging and exhausting air of the camshafts 35 for valve systemsfor the above four cylinders 2 a, 2 b, 2 c, 2 d and the phase of camsfor charging and exhausting air of the camshafts 35 for valve systemsfor the other four cylinders 2 e, 2 f, 2 g, 2 h so that four cylinderson the same circumference are in compression stroke while the other fourcylinders are in exhaust stroke when the eight cylinders are all movingupward, and four cylinders on the same circumference are in power strokewhile the other four cylinders are in intake stroke when the eightcylinders are all moving downward.

Further, the cams for charging and exhausting air of the camshafts 35for valve systems corresponding to two cylinders 2 a and 2 c on theouter circumference 50 and two cylinders 2 e and 2 g or 2 f and 2 h onthe inner circumference 51 may be designed to have the same magnitudeand direction for the opening or closing angle, so that the fourcylinders intake, compress, work and exhaust in synchronism, while camsfor charging and exhausting air of the camshafts 35 for valve systemscorresponding to the other two cylinders 2 b and 2 d on the outercircumference 50 and the other two cylinders 2 f and 2 h or 2 e and 2 gon the inner circumference 51 may be designed to have the same magnitudeand direction for the opening or closing angle, so that the other fourcylinders intake, compress, work and exhaust in synchronism. It isdesigned to have a difference of 180 degrees between the phase of camsfor charging and exhausting air of the camshafts 35 for valve systemsfor the former four cylinders and the phase of cams for charging andexhausting air of the camshafts 35 for valve systems for the latter fourcylinders so that four cylinders are in compression stroke while theother four cylinders are in exhaust stroke when the eight cylinders areall moving upward, and four cylinders are in power stroke while theother four cylinders are in intake stroke when the eight cylinders areall moving downward.

In the Embodiment 5 and 7, bevel gears 40 that are disposed at one endof each of the four camshaft 35 for valve systems of the above fourcylinder covers 28 all engage with the bevel gear 47 that is disposed atthe upper end of the transmission shaft 48 which extends upwardly fromthe center of the upper end of the internal groove cam 6 b via thethrough hole 55 at the center of the four-leg roller shaft 16 b. Thepistons reciprocate eight times when the internal groove cam 6 b with acam groove having four peaks and four valleys rotates for one round, andat the same time, each cylinder works twice, that is, an internalcombustion engine having four cylinders works eight times, or aninternal combustion engine having eight cylinders works sixteen times.It is apparent that efficiency of the cylinder and power per liter in aninternal combustion engine using present invention are improved fourtimes.

In the above Embodiment 3 to 7, it can be seen that there is adifference of 180 degree between the phase angle of the cams forcharging and exhausting air with the same opening or closing angle ofthe valves corresponding to one half of the total cylinders and that ofthe cams for charging and exhausting air with the same opening orclosing angle of the valves corresponding to the other half of the totalcylinders, so that one half of the total cylinders are in power strokewhile the other half of the total cylinders are in intake stroke whenall pistons are moving downward, and one half of the total cylinders arein exhaust strokes while the other half of the total cylinders are incompression stroke when all pistons are moving upward.

In the above Embodiment 2 to 7, the cylinder covers 28 of the internalcombustion engine have intake pipes connected at the intake ports, andexhaust pipes and muffles connected at the exhaust ports.

One of the important ways to improve the power of the engine is toincrease the amount of intake air. Although it is usual to utilize aturbocharger in a modern internal combustion engine for increasing airpressure, the cost is high. When the piston rods of the internalcombustion engine according to the present invention reciprocate up anddown, the volume under the piston varies and the air pressure changesaccordingly. Thus, the cylinder will function as a pump only if it isprovided with a one-way intake valve and a one-way exhaust valve so thatthe amount of intake air will increase. Therefore, a one-way intakevalve 69 and a port 75 of the intake pipe communicating with the air,and a one-way exhaust valve 70 and a port 76 of the exhaust pipecommunicating with the air are provided in the side hole 45 in thecylinder 1 or the cam box 15, as shown in FIG. 17. When the piston rods5 move upward, vacuum is generated in the sealed cavity under the pistonso that air is charged from the intake valve 69. When the piston rods 5move downward, the air under the piston is pressurized into the cylinderthrough the exhaust valve 70. The air pressure changes in the sealedcavity under the piston rods also may be used as a power source to drivea free piston 71 or a membrane of an air driven reciprocating pump 73having a free piston or a membrane in the side hole 45 in the cylinderand the cam box. Then air is pressurized into the cylinder through theone-way intake valve 69 on the one-way valve cover 77, then through theone-way exhaust valve 70 and an pipe directing to the intake port of thecylinder cover 28, as shown in FIGS. 17 a and 17 b, so that theefficiency of air pumping is improved as the cost is lowered.

The internal combustion engine as described in the above Embodiments 1to 7 is such an gasoline internal combustion engine which is equippedwith a gasoline pump, a carburetor or a gasoline supply system having anelectronic controlled injection nozzle in the intake manifold and thelike, and an ignition system having spark plugs, spark wires andjump-spark coils on the cylinder cover, or such an diesel internalcombustion engine which is equipped with a high pressure injection pump,and an fuel supply system having high pressure injection nozzle.

The internal combustion engine as described in Embodiments 1 to 7 isprovided with a ring gear at the lower part of the outer circumferenceof the internal groove cam and a starter motor at the position oppositeto the cam box 15 in order to start the internal combustion engine.

The internal combustion engine as described in Embodiment 1 to 7 may becooled by air, or water by a water pump, a water tank or a fan mountedtherein.

Embodiment 8

A sterling engine comprises a power transmission mechanism having aninternal groove cam as shown in FIG. 18 a. The engine comprises two setsof power transmission mechanism having an internal groove cam in asingle cylinder, a heater 56, a recuperator 57, and a cooler 58. The twointernal groove cams 6 in the two sets of power transmission mechanismhaving an internal groove cam in a single cylinder engage with eachother by means of a gear 42 in parallel manner so as to transmit power.An air port 19 on one of the cylinder covers 28 communicates with theheater 56, and an air port 19 on the other cylinder cover 28communicates with the cooler 58. The heater 56 and the cooler 58 bothcommunicate with the recuperator 57 as shown in the FIG. 21. FIG. 18 bshows the circumferentially stretched phase of the two primary rollers 9disposed near both ends of the roller shafts connected with the lowerpart of the two piston rods 5 a 2 a in the two sets of powertransmission mechanism having an internal groove cam in a singlecylinder, and rolling on the lower circumferential cam contour 8 of theinternal groove cam 6. As shown in FIG. 6 b 1, when using the internalgroove cam 6 having a circumferential cam contour with two upperstopping peaks and two valleys, a two-leg piston rod 5 b 2 a and aroller shaft 16 are used. As shown in FIG. 6 a, when using the internalgroove cam 6 having a circumferential cam contour with three upperstopping peaks and three valleys, a three-leg piston rod 5 b 3 and aroller shaft 16 a are used. As shown in FIG. 6 c, when using theinternal groove cam 6 having a circumferential cam contour with fourupper stopping peaks and four valleys, a four-leg piston rod 5 b 2 a anda roller shaft 16 b are used. More than two sets of the powertransmission mechanism having an internal groove cam may be used toconstitute a multi-cylinder sterling engine by means of geartransmission.

Embodiment 9

A pneumatic or hydraulic motor comprises a power transmission mechanismhaving an internal groove cam. The motor comprises two sets of powertransmission mechanism having an internal groove cam in a singlecylinder, a transmission gear 38, a reversing gear 66, a reversing valve60, a transmission shaft 59. The transmission gears 38 respectivelymounted in the two sets of power transmission mechanism engage theintermediate reversing gear 66 in parallel manner to transmit power,wherein the intermediate gear 66 includes one end as the output shaft ofthe pneumatic motor, and the other end which links the reversing valve60 located on the cylinder cover by means of the transmission shaft 59.Air channels 64 communicating with the reversing valve 60 are connectedto the air ports 19 of the two cylinders 28 as shown in FIG. 19 a. FIG.19 b shows the circumferentially stretched phase of the two primaryrollers 9 near two ends of the roller shaft located at the lower part ofthe two piston rods 5 in the two sets of the power transmissionmechanism having an internal groove cam in a single cylinder, in whichthe rollers roll on the lower circumferential cam contour 8 of theinternal groove cam 6.

The above two internal groove cams both have the same two peaks and twovalleys, or three peaks and three valleys, or four peaks and fourvalleys, and the projecting circumferential angle of the power curve 31of the circumferential cam contour is greater than that of the exhaustcurve 32 of the circumferential cam contour, so that once certain amountof working medium enters into from the intake port, the pneumatic orhydraulic motor will output torque power without dead point. More thantwo sets of the power transmission mechanism may be used to constitute amulti-cylinder pneumatic or hydraulic motor by means of geartransmission.

The maximum pressure angle in the rising curve 31 and descending curve32 of the circumferential cam contour of the internal groove cam in theabove embodiments may be designed to range from 40 to 80 degree, and islocated at approximately the middle of the paths.

Embodiment 10

A pneumatic or hydraulic pump comprises a power transmission mechanismfor conversion between linear movements and rotary motions. The pumpcomprises an internal groove cam 6, a roller shaft 16, a piston 5, apiston rod 5 a 2 a, primary rollers 9, secondary rollers 37, guidingrollers or sliding blocks 27, a cylinder cover 28 having an intake valve69 and an exhaust valve 70, a cylinder 1 having a cylinder opening 2,fixed guide rails 4, and a cam box 15. The internal groove cam 6 isprovided in the cam box 15. The cylinder 1 having the cylinder openingand the cylinder cover 28 is fixed to the cam box 15 above the upperpart of the cam. The lower part of the piston rod 5 a 2 a fixed to thepiston 5 in the cylinder opening 2 is mounted on the roller shaft 16.Two primary rollers 9 and two secondary rollers 37 are disposed near thetwo ends of the roller shaft at the positions corresponding to thecircumferential cam contour so that they are received in the groove ofthe internal groove cam through two slots 12 in the uppercircumferential cam contour of the internal groove cam 6 to rollfollowing the circumferential contour, which forms a non-cantileveredstructure freely supported at two ends. Two guiding rollers or slideblocks 27 are further disposed on the roller shaft at correspondingpositions to the fixed guide rails 4 connected with the lower end of thecylinder 1 in the axial direction of the internal groove, as shown inFIG. 20. The piston 5 will reciprocate up and down when external forcedrives the internal groove cam to rotate, so that the air or liquid inthe cavity above the piston will be drawn in through the intake valve69, and exhausted out through the exhaust valve 70.

Sliding bearings (rolling bearings are not excluded) are disposedbetween the lower part of the internal groove cam and the end surfacebearing, and between the sliding blocks and the fixed guide rails, sothat they may be lower plane kinematical pair which has enough area inorder to use pressurized lubricant oil as oil pad to support theinternal groove cam and the sliding blocks for improving efficiency. Apart of lubricant system and oil path are as follows: the pressurizedoil is outputted from the oil pump 42 by the output shaft at the lowerpart of the internal groove cam to the lower end surface of the internalgroove cam and a through hole 61, then pass ring channel 33 a 1 of theupper end surface bearing 33 a and a through hole extending upward to athrough hole 66 on the surface of the fixed guide rail 4, as shown inFIG. 3. Then, the sliding block 27 seal the hole 66. If rolling bearingsare used for the primary roller 9 and the secondary roller 37, a smallnozzle hole 78 is disposed on the side surface of the fixed guide railseat 4 d to communicate with the oil path, in order to enable the rollershaft to rise to about half the height, so that lubricant oil from thenozzle hole 78 sprays to the primary rollers 9 to lubricate and coolthem, as shown in FIG. 10 a. If sliding bearings are used for theprimary rollers 9, the sliding surface of the sliding block 27 may beprovide with a hole directing to the central hole of the roller shaft,and the roller shaft may be provided with a hole directing to thecentral hole of the roller shaft for lubricating and cooling the primaryrollers 9, which is located at a position where the primary rollers 9are installed, as shown in FIG. 10 b.

When being installed near either outer end of the roller shaft, theprimary rollers 9 and the secondary rollers 37 may be positioned by asnap ring 18. After the primary and secondary rollers are received inthe groove of the internal groove cam through the slot 12 in the uppercircumferential cam contour 7, an enclosing block 13 may be used to sealeach of the slots 12 by a screw 23 when needed.

In the internal combustion engine, sterling engine, pneumatic orhydraulic motor having the power transmission mechanism having aninternal groove cam as described above, there are an openable seal coverand a hole 55 communicating with outside provided in inner side of thecam box 15 at the position corresponding to the side hole 22 of theinternal groove cam or the slot 12 for removing or installing theprimary roller 9 and the secondary roller 37 from or to the roller shaftby exposing the hole 45, removing the seal block 13 and snap ring 18without disassembling the cylinder.

An engine comprising the power transmission mechanism having an internalgroove cam may be used in traveling vehicles (such as vehicle, ship, aircraft and the like) used in the air, water or on the land, or poweroutputting machines to provide power.

1. A power transmission mechanism for conversion between linearmovements and rotary motions, comprising: an internal groove cam capableof rotating about an axis thereof, comprising a continuous cam grooveformed in the wall of a cylindrical inner cavity formed by the internalgroove cam; a cam box accommodating and supporting the internal groovecam, which comprises a cover on the top thereof and a fixed rail mountedbelow the cover and extending into the cylindrical inner cavity formedby the internal groove cam; an assembly for linear reciprocatingmovement including: a roller shaft provided perpendicular to the axis ofthe internal groove cam, a primary roller and a secondary roller mountedadjacent to each other at each end of the roller shaft, both rollersmounted into the cam groove for rolling in the cam groove, and a guidingmember provided on the roller shaft and moving along the rail, whereinthe primary roller, the secondary roller and the roller shaft form anon-cantilevered structure freely supported at least at two ends thereofin the internal groove cam; wherein the primary roller and the secondaryroller move in the cam groove, in conjunction with the simultaneousmovement of the guiding member along the fixed rail, to actuate themovement of the roller shaft.
 2. A power transmission mechanism forconversion between linear movements and rotary motions according toclaim 1, wherein the guiding member is a roller or a sliding block.
 3. Apower transmission mechanism for conversion between linear movements androtary motions according to claim 1, wherein the cover is provided by acylinder having a cylinder opening, in which a piston having a pistonrod is received, the piston rod of the piston being connected to thepiston at one end and to the roller shaft at the other end.
 4. A powertransmission mechanism for conversion between linear movements androtary motions according to claim 3, wherein one of the upper camcontour and the lower cam contour has at least two slots for receivingthe roller shaft into the cam groove.
 5. A power transmission mechanismfor conversion between linear movements and rotary motions according toclaim 3, wherein the roller shaft includes n segments irritating fromthe center to the periphery and spaced circumferentially at equal angle,and n fixed rails are formed corresponding to the n segments, n being aninteger between 2 to
 5. 6. A power transmission mechanism for conversionbetween linear movements and rotary motions according to claim 5,wherein the piston rod has n legs being connected to correspondingsegments of the roller shaft respectively.
 7. A power transmissionmechanism for conversion between linear movements and rotary motionsaccording to claim 5, wherein the piston has n piston rods beingconnected to the corresponding segments of the roller shaftrespectively, and the cylinder has n cylinder openings.
 8. A powertransmission mechanism for conversion between linear movements androtary motions according to claim 5, wherein n cylinders are provided tocorrespond to the segments of the roller shaft respectively, each ofwhich has a piston, a piston rod and a cylinder opening, the piston rodbeing connected to the corresponding segment of the roller shaft.
 9. Apower transmission mechanism for conversion between linear movements androtary motions according to claim 8, wherein the power transmissionmechanism for conversion between linear movements and rotary motionscomprises a single-cylinder and double-stroke internal combustionengine, in which n is
 2. 10. A power transmission mechanism forconversion between linear movements and rotary motions according toclaim 8, wherein the power transmission mechanism for conversion betweenlinear movements and rotary motions comprises a single-cylinder andfour-stroke internal combustion engine, in which n is
 2. 11. A powertransmission mechanism for conversion between linear movements androtary motions according to claim 8, wherein the power transmissionmechanism for conversion between linear movements and rotary motionscomprises a four-cylinder and four-stroke internal combustion engine, inwhich n is
 4. 12. A power transmission mechanism for conversion betweenlinear movements and rotary motions according to claim 5, wherein saidcylinder is provided with m cylinder openings for each segment of theroller shaft so that the amount of the cylinders opening is m×n intotal, a piston and a piton rod being disposed to correspond to eachcylinder opening, the piston rod being connected to the correspondingsegment of the roller shaft and the m being 1 or
 2. 13. A powertransmission mechanism for conversion between linear movements androtary motions according to claim 12, wherein the power transmissionmechanism for conversion between linear movements and rotary motionscomprises a double-cylinder and four-stroke inline internal combustionengine, in which n is 2 and m is
 1. 14. A power transmission mechanismfor conversion between linear movements and rotary motions according toclaim 12, wherein the power transmission mechanism for conversionbetween linear movements and rotary motions comprises a four-cylinderand four-stroke inline internal combustion engine, in which n is 2 and mis
 2. 15. A power transmission mechanism for conversion between linearmovements and rotary motions according to claim 1, wherein the internalgroove cam has a rotary shaft, and the cam groove has a contour curvehaving at least two peaks and two valleys with the same amplitude, andcomprises an upper cam contour and a lower cam contour, the primaryrollers and the secondary rollers rolling between them.
 16. A powertransmission mechanism for conversion between linear movements androtary motions according to claim 15, wherein the internal groove cam iscombined and fixed to each other by two parts which have the upper camcontour and the lower cam contour, respectively.
 17. A powertransmission mechanism for conversion between linear movements androtary motions according to claim 15, wherein the downward projectionimage of the working contour of the upper cam contour does not overlapthe working contour of the lower cam contour, or does not coincidecompletely therewith.
 18. A power transmission mechanism for conversionbetween linear movements and rotary motions according to claim 15,wherein the secondary rollers contact and engage with the upper camcontour of the internal groove cam, and the primary rollers contact andengage with the lower cam contour of the internal groove cam.
 19. Apower transmission mechanism for conversion between linear movements androtary motions according to claim 15, wherein the upper cam contourand/or the lower cam contour are inward-tipping with respect to theinner portion of the cam grooves.
 20. A power transmission mechanism forconversion between linear movements and rotary motions according toclaim 1, wherein the maximum pressure angle of the rising curve or thedescending curve in the circumferential cam contour curve of theinternal groove cam is designed to range from 40 to 80 degree.